Ahmad Muzammil, Pyaram Kalyani, Mullick Jayati, Sahu Arvind
National Centre for Cell Science, Pune University Campus, Ganeshkhind, Pune 411 007, India.
Indian J Biochem Biophys. 2007 Oct;44(5):331-43.
The complement system is a principal bastion of innate immunity designed to combat a myriad of existing as well as newly emerging pathogens. Since viruses are obligatory intracellular parasites, they are continuously exposed to host complement assault and, therefore, have imbibed various strategies to subvert it. One of them is molecular mimicry of the host complement regulators. Large DNA viruses such as pox and herpesviruses encode proteins that are structurally and functionally similar to human regulators of complement activation (RCA), a family of proteins that regulate complement. In this review, we have presented the structural and functional aspects of virally encoded RCA homologs (vRCA), in particular two highly studied vRCAs, vaccinia virus complement control protein (VCP) and Kaposi's sarcoma-associated herpesvirus complement regulator (kaposica). Importance of these evasion molecules in viral pathogenesis and their role beyond complement regulation are also discussed.
补体系统是固有免疫的主要堡垒,旨在对抗众多现存以及新出现的病原体。由于病毒是专性细胞内寄生虫,它们不断受到宿主补体的攻击,因此,已经采用了各种策略来颠覆补体系统。其中之一是对宿主补体调节因子的分子模拟。痘病毒和疱疹病毒等大型DNA病毒编码的蛋白质在结构和功能上与人类补体激活调节因子(RCA)相似,RCA是一类调节补体的蛋白质。在这篇综述中,我们介绍了病毒编码的RCA同源物(vRCA)的结构和功能方面,特别是两种经过深入研究的vRCA,痘苗病毒补体控制蛋白(VCP)和卡波西肉瘤相关疱疹病毒补体调节因子(kaposica)。还讨论了这些逃避分子在病毒发病机制中的重要性及其在补体调节之外的作用。